12726: Add migrations avatar test for GogsDownloader.

- Fix potential bug where forward-slash can be missing from URL to avatar.

services/migrations/gogs.go

@@ -142,7 +142,7 @@ func (g *GogsDownloader) GetRepoInfo() (*base.Repository, error) {
 		return nil, err
 	}
 
-	avatarURL := fmt.Sprintf("%srepo-avatars/%d", g.baseURL, gr.ID)
+	avatarURL := fmt.Sprintf("%s/repo-avatars/%d", strings.TrimRight(g.baseURL, "/"), gr.ID)
 
 	// convert gogs repo to stand Repo
 	return &base.Repository{

services/migrations/gogs_test.go

@@ -9,6 +9,7 @@ import (
 	"testing"
 	"time"
 
+	"forgejo.org/models/unittest"
 	base "forgejo.org/modules/migration"
 
 	"github.com/stretchr/testify/assert"
@@ -222,3 +223,29 @@ func TestGogsDownloaderFactory_New(t *testing.T) {
 		})
 	}
 }
+
+func TestGogsDownloaderAvatarDownload(t *testing.T) {
+	GithubLimitRateRemaining = 3 // Wait at 3 remaining since we could have 3 CI in //
+
+	token := os.Getenv("GOGS_READ_TOKEN_BIRDGOOSE")
+	liveMode := token != ""
+
+	fixturePath := "./testdata/gogs/avatar"
+	server := unittest.NewMockWebServer(t, "https://try.gogs.io", fixturePath, liveMode)
+	defer server.Close()
+
+	downloader := NewGogsDownloader(t.Context(), server.URL, "", "", token, "example", "example-repo")
+
+	repo, err := downloader.GetRepoInfo()
+	require.NoError(t, err)
+
+	assertRepositoryEqual(t, &base.Repository{
+		Name:          "example-repo",
+		Owner:         "example",
+		Description:   "An example repo for Forgejo migration testing.",
+		CloneURL:      server.URL + "/example/example-repo.git",
+		OriginalURL:   server.URL + "/example/example-repo",
+		DefaultBranch: "main",
+		AvatarURL:     server.URL + "/repo-avatars/99330",
+	}, repo)
+}

services/migrations/testdata/gogs/avatar/GET_%2Fapi%2Fv1%2Frepos%2Fexample%2Fexample-repo

@@ -0,0 +1,10 @@
+Alt-Svc: h3=":443"; ma=86400
+Cf-Cache-Status: DYNAMIC
+Content-Type: application/json; charset=UTF-8
+Server-Timing: cfCacheStatus;desc="DYNAMIC"
+Server-Timing: cfEdge;dur=11,cfOrigin;dur=628
+Strict-Transport-Security: max-age=15552000; includeSubDomains
+X-Content-Type-Options: nosniff
+X-Frame-Options: deny
+
+{"id":99330,"owner":{"id":126484,"username":"example","login":"example","full_name":"","email":"full.stick1536@foo.nz","avatar_url":"https://secure.gravatar.com/avatar/4468e916c63945b1907c28851dd7a678?d=identicon"},"name":"example-repo","full_name":"example/example-repo","description":"An example repo for Forgejo migration testing.","private":false,"fork":false,"parent":null,"empty":true,"mirror":false,"size":0,"html_url":"https://try.gogs.io/example/example-repo","ssh_url":"git@ssh.try.gogs.io:example/example-repo.git","clone_url":"https://try.gogs.io/example/example-repo.git","website":"","stars_count":0,"forks_count":0,"watchers_count":1,"open_issues_count":0,"default_branch":"main","created_at":"2026-06-02T10:43:34Z","updated_at":"2026-06-02T10:43:34Z","permissions":{"admin":true,"push":true,"pull":true}}